Switches & Buttons#
Goal. Build a simple circuit where pressing a button or flipping a switch turns an LED on. This introduces the concept of control in an electronic circuit.
Instructions for TinkerCAD#
Components#
- Breadboard
- 1 LED (any color)
- 1 resistor (220Ω or 330Ω)
- 1 push button or toggle switch (SPST)
- Jumper wires
- Battery holder with batteries (e.g. 2xAA or 9V)
Step-by-Step Instructions#
-
Set Up the LED (Same as Last Time)#
- Insert the LED into the breadboard (long leg in one row, short leg in another).
- Connect a 220Ω resistor to the short leg (–) of the LED and plug the other end into a separate row.
-
Add the Button or Switch#
- Place the push button across the central divide of the breadboard (the two sides of the breadboard are separated underneath).
- OR, insert the two terminals of the switch into different rows if using a toggle switch.
-
Wire the Power Through the Switch#
- Connect the positive (red) wire from the battery pack to one side of the button/switch.
- Use a jumper wire to connect the other side of the button/switch to the row with the long leg of the LED.
-
Complete the Circuit#
- Connect the row with the other end of the resistor (from the LED) to the negative (black) wire from the battery.
-
Test It!#
- Turn on the battery.
- Now, press the button or flip the switch.
- The LED should light up only when the button is pressed or the switch is on.
What you’ve learned#
- Buttons and switches interrupt or complete the circuit.
- The LED only lights when electricity can flow all the way through.
- Buttons are momentary (only work while pressed). Switches can stay on/off.
Try this#
- Replace the button with a toggle switch and observe the difference.
- (Challenge) Add two LEDs: can you make one turn on when the switch is on, and the other when it’s off?